COMPLEX I SUBUNITS
MITOCHONDRIAL DNA ANALYSIS

Description:

Complex I (NADH dehydrogenase complex) deficiency is the most common mitochondrial respiratory chain defect, and can be caused by both nuclear and mitochondrial encoded genes. Among the 46 protein subunits, seven are encoded by the mitochondrial genome. Mutations in mtDNA encoded complex I genes have been found in patients with Leber’s Hereditary Optic Neuropathy (LHON), MELAS syndrome, and bipolar disorder. In addition to primary mutations, several missense polymorphisms have been reported to cause synergistic effect on the pathogenesis of LHON. Certain mitochondrial DNA haplogroups determined by SNPs in complex I genes may increase the risk of neurodegenerative diseases such as Parkinson and Alzheimer diseases.

Reasons for Referral:

To confirm the diagnosis of mitochondrial disease caused by mutations in mitochondrial encoded complex I subunit genes.

Testing Methodology:

The mitochondrial DNA regions encoding complex I subunits are PCR amplified and sequenced.

Sensitivity:

In general, sequence analysis does not detect low mutant heteroplasmy. Sometimes heteroplasmy <50% may not be detected.

Specimen Requirements:

100 mg of tissue or blood.
Tissue: strongly prefer skeletal muscle; heart, brain, liver, kidney or fibroblast cultures also accepted.
Blood: EDTA (purple-top) tubes: Adult: 14 cc; Child: 6 cc; Infant: 2-3 cc

Turnaround Time:

Index: 4 weeks
Known Familial Mutation: 2 weeks

CPT Codes and Prices:

Index: 83904x24, 83898x8, 83912, 83891
Known Familial Mutation: 83904x4, 83898x2, 83912, 83891, 83894x2

Shipping Information

Forms:

>> Mitochondrial Requisition - Mitochondrial Diagnostic Checklist is included

Test Codes:

Index: 3050
Known Familial Mutation: 3051